1. Field of the Invention
This invention relates, generally, to poultry processing devices. More particularly, it relates to a poultry cropper machine that removes contaminates from poultry through a timely and efficient use of water.
2. Description of the Prior Art
Poultry crop removing machines remove the crop and other viscera from previously slaughtered poultry animals such as chickens.
These machines typically include a shackle from which a previously slaughtered chicken or other poultry animal is suspended by its legs. The head and feathers of the animal are removed prior to the time it is attached to the shackle. A rotating device having teeth, known as a cropper, is introduced in a first direction into the chicken's vent and advanced through the digestive system thereof until it exits the chicken through the neck. The cropper removes the esophagus, the ingluvius (crop), and other viscera of the chicken, leaving an internal cavity where such viscera had been. The cropper is withdrawn from the internal cavity by displacing it in a second direction opposite to the first. The eviscerated poultry animal is then transported to a cleaning station where a cleaning device is inserted into the internal cavity to spray it with water for cleanliness purposes.
The advancement of the cropper through the body is a downward motion and the retraction of the cropper from the body requires an upward motion. An endless chain of shackles is driven by a drive means that brings the shackles to the crop removing machine, and the same endless chain carries the eviscerated poultry animals to the cleaning station.
The up and down motion of the cropper is achieved by a camming action. Specifically, the crop-removing machine includes a non-rotating frusto-conical drum having a vertical axis of symmetry. A first downwardly sloping helical deflection plate is secured to the drum. The downwardly sloping deflection plate slideably engages a protuberance that extends from a block so that the block is displaced downwardly as it rotates past the drum. The block is carried by the same drive system that carries the shackles and therefore it moves conjointly therewith. The block carries an elongate rod, known as a spiral rod, downwardly as the block is displaced downwardly by the deflection plate. The crop-removing means is formed at the lowermost end, or leading end, of the spiralted so that the crop-removing means enters the bird at its vent and exits through the neck opening during the downward stroke.
A second, upwardly sloping helical deflection plate is mounted to the drum such that its lowermost end is near the lowermost end of the downwardly sloping deflection plate. Accordingly, the protuberance formed in the block disengages from the downwardly sloping deflection plate at its lowermost end and enters into sliding engagement with the upwardly sloping deflection plate as the block follows its predetermined path of travel. This drives the block and the spiral rod upwardly so that the crop-removing means re-enters the chicken at its neck opening and exits the chicken at the vent.
The crop-removing means is typically washed with a spray of chlorinated water and a brush after it exits the neck opening on the downward stroke and again after it exits the vent on the upward stroke so that it is clean before it enters the vent of the next chicken. The brush removes the viscera from the cropper.
The block also includes a rotation means to rotate the spiral rod about its longitudinal axis of symmetry as it alternately travels upwardly and downwardly. This rotates the cropper so that teeth formed therein can better grasp the viscera and remove it. A helix is formed along a predetermined extent of the spiral rod and the helix engages a cam means within the block that effects the desired rotation of the spiral rod as it reciprocates up and down.
The primary drawback of the current apparatus, described above, is that the viscera is removed at a crop-removing station, and the interior cavity of the bird is not washed until later, at a washing station. Thus, contaminates in the interior cavity have time to become absorbed into tissue surrounding the cavity and no amount of water can properly clean the contaminates from the bird.
Processing plant owners typically request chicken farmers to turn off their chickenfeeding machines about twenty four hours before delivering the birds to the processing plant so that the stomachs of the chickens will be substantially empty upon their arrival at the plant. A bird with an empty stomach is more easily cleaned and made safe for human consumption. However, some farmers continue to feed their chickens right up to delivery time, because the chickens are sold by weight and the farmer desires a maximum payment. When a recently-fed chicken is processed, its stomach and bowel contents may be splattered about during the viscera removal process, and chickens suspended from adjacent shackles may be contaminated thereby. This requires the entire lot of chickens to be rejected for human use because no amount of water can safely and effectively clean the recently-fed chicken and the nearby chickens that may have been splattered with fecal matter and the like.
However, even when all of the chickens being processed have not been fed during the twenty four hours preceding their delivery to the processing plant, the known methods of removing the crop and other viscera and thereafter washing the interior of the bird are still inadequate because they are wasteful of water and too much time is allowed to elapse between viscera removal and interior cavity washing.
U.S. Pat. No. 3,137,031 to Ine et al. describes a method for cleaning poultry during an evisceration procedure. The method employs a device that has a simultaneous water spray and vacuum to flush and remove fecal matter from the intestines of poultry. However, the method is manually operated and is performed before the removal of any viscera or to any handling or disturbance of the bowel regions of the bird (column 4, lines 29-34). Thus, contaminates that may be spread throughout the internal cavity are not washed out after viscera removal.
U.S. Pat. No. 4,106,161 to Niccolls describes a poultry cleaning apparatus and method specifically for use after ingesta or fecal matter has been released in the abdominal cavity of the bird. This invention aims to sufficiently clean a contaminated bird that would normally be condemned for human consumption (column 1, lines 22-25). However, the structure that embodies this invention is manually operated and has utility only after contamination has occurred.
U.S. Pat. No. 4,876,767 to Harben, III et al. describes a vent cleaning apparatus and method for preparing poultry. A hollow suction probe enters the vent of the bird and a flow of water is introduced in the vicinity of the probe opening to provide a mass flow sufficient to transport loose fecal matter into the suction opening of the probe. However, the system does not relate to the removal of the viscera, but simply to the initial preparation of the bird for evisceration (column 2, lines 27-30).
U.S. Pat. No. 4,899,421 to Van Der Eerden describes another method and apparatus for removing fecal matter in poultry. The method and apparatus is applied to an automated system, but remains a separate step from the evisceration process (column 1, lines 41-48).
U.S. Pat. No. 5,041,054 to van den Nieuwelaar et al. describes a device and method for washing poultry comprising a spraying element to which cleaning liquid can be fed, and radially projecting parts, running primarily in the lengthwise direction, being disposed near the spraying element, which parts are provided with sharp projections. However, these projections are not used to remove the crop but rather to pierce and/or dislodge respiratory system membranes in the bird which may accumulate polluted cleaning liquid during the washing process (column 1, lines 38-48).
What is needed, then, is an automatic apparatus that reduces water consumption during the crop/viscera removal process. Moreover, it would be beneficial if a way could be found to combine the evisceration process and the cleaning process into one step. That would simplify the de-cropping machinery, reducing its cost and making its operation more reliable.
However, it was not obvious to those of ordinary skill in this art how the needed improvements could be provided, in view of the art considered as a whole at the time the present invention was made.